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<HEAD><TITLE>smfi_addheader</TITLE></HEAD>
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$Id: smfi_addheader.html,v 1.21 2013-11-22 20:51:39 ca Exp $
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<H1>smfi_addheader</H1>

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<!---------- Synopsis ----------->
<TR><TH valign="top" align=left width=100>SYNOPSIS</TH><TD>
<PRE>
#include &lt;libmilter/mfapi.h&gt;
int smfi_addheader(
	SMFICTX *ctx,
	char *headerf,
	char *headerv
);
</PRE>
Add a header to the current message.
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<!----------- Description ---------->
<TR><TH valign="top" align=left>DESCRIPTION</TH><TD>
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<TH width="80">Called When</TH>
<TD>Called only from <A href="xxfi_eom.html">xxfi_eom</A>.</TD>
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<TR align="left" valign=top>
<TH width="80">Effects</TH>
<TD>Adds a header to the current message.</TD>
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<!----------- Arguments ---------->
<TR><TH valign="top" align=left>ARGUMENTS</TH><TD>
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    <TR bgcolor="#dddddd"><TH>Argument</TH><TH>Description</TH></TR>
    <TR valign="top"><TD>ctx</TD>
	<TD>Opaque context structure.
	</TD></TR>
    <TR valign="top"><TD>headerf</TD>
	<TD>The header name, a non-NULL, null-terminated string.
	</TD></TR>
    <TR valign="top"><TD>headerv</TD>
	<TD>The header value to be added, a non-NULL, null-terminated string.
	This may be the empty string.
	</TD></TR>
    </TABLE>
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<!----------- Return values ---------->
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<TH valign="top" align=left>RETURN VALUES</TH>

<TD>smfi_addheader returns MI_FAILURE if:
<UL><LI>headerf or headerv is NULL.
    <LI>Adding headers in the current connection state is invalid.
    <LI>Memory allocation fails.
    <LI>A network error occurs.
    <LI><A HREF="smfi_register.html#SMFIF_ADDHDRS">SMFIF_ADDHDRS</A> is not set.
</UL>
Otherwise, it returns MI_SUCCESS.
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<!----------- Notes ---------->
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<TH>NOTES</TH>
<TD>
<UL><LI>smfi_addheader does not change a message's existing headers.
To change a header's current value, use
<A HREF="smfi_chgheader.html">smfi_chgheader</A>.
    <LI>A filter which calls smfi_addheader must have set the
        <A HREF="smfi_register.html#SMFIF_ADDHDRS">SMFIF_ADDHDRS</A> flag.
    <LI>For smfi_addheader, filter order is important.
	<B>Later filters will see the header changes made by earlier ones.</B>
    <LI>Neither the name nor the value of the header is checked for
    standards compliance.
    However, each line of the header must be under 2048 characters
    and should be under 998 characters.
    If longer headers are needed, make them multi-line.
    To make a multi-line header,
    insert a line feed (ASCII 0x0a, or <TT>\n</TT> in C)
    followed by at least one whitespace character
    such as a space (ASCII 0x20) or tab (ASCII 0x09, or <TT>\t</TT> in C).
    The line feed should NOT be preceded by a carriage return (ASCII 0x0d);
    the MTA will add this automatically.
    <B>It is the filter writer's responsibility to ensure that no standards
    are violated.</B>
    <LI>The MTA adds a leading space to an added header value unless
    the flag
<A HREF="xxfi_negotiate.html#SMFIP_HDR_LEADSPC"><CODE>SMFIP_HDR_LEADSPC</CODE></A>
    is set, in which case the milter
    must include any desired leading spaces itself.
</UL>
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<!----------- Example code ---------->
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<TH valign="top" align=left>EXAMPLE</TH>

<TD>
 <PRE>
  int ret;
  SMFICTX *ctx;

  ...

  ret = smfi_addheader(ctx, "Content-Type",
                       "multipart/mixed;\n\tboundary=\"foobar\"");
 </PRE>
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Copyright (c) 2000-2003, 2006, 2009 Proofpoint, Inc. and its suppliers.
All rights reserved.
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By using this file, you agree to the terms and conditions set
forth in the LICENSE.
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